Galera test galera_parallel_apply_3nodes is unstable

URRENT_TEST: galera_3nodes.galera_parallel_apply_3nodes

--- /home/jan/mysql/10.5/mysql-test/suite/galera_3nodes/r/galera_parallel_apply_3nodes.result	2022-09-05 13:24:32.564866767 +0300

+++ /home/jan/mysql/10.5/mysql-test/suite/galera_3nodes/r/galera_parallel_apply_3nodes.reject	2022-10-12 11:44:45.163220780 +0300

@@ -18,6 +18,8 @@

 UPDATE t1 SET f1 = f1 + 100;;

 connection node_1_ctrl;

 SET DEBUG_SYNC = 'now WAIT_FOR wsrep_retry_autocommit_reached';

+Warnings:

+Warning	1639	debug sync point wait timed out

 SET GLOBAL debug_dbug = NULL;

 SET DEBUG_SYNC = 'now SIGNAL wsrep_retry_autocommit_continue';

 connection node_1;

mysqltest: Result length mismatch